Note 12 - Goodwill and Intangible Assets - Summary of Changes in Goodwill (Details) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($)
Goodwill, Net additions	$ 1,069
Goodwill	(229)
Goodwill, gross	1,551
Accumulated goodwill impairmant	(99)
Goodwill	612
Goodwill	$ 1,452

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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